RICO is a big part of it. But it comes down to RECRUITMENT, RECRUITMENT, RECRUITMENT.
When it comes to Cosa Nostra in the US, they just don't have that pool of guys they can reach back and grab. The values have changed here, they aren't as closely aligned with the old country as they are in Canada.
As someone mentions, there was/is still a large influx of immigrants coming over into Canada from various parts of Italy.
A lot of the families have transferred that allegiance into Canada, with family still operating in Italy. That's a huge advantage.
I do think several US families still keep in contact with both Sicily and Calabria. It's just that violence and murders are less common nowadays.
